Site selection for Haloxylon ammodendron plantation based on soil factors

The success of plantation, establishment, and growth of trees and shrubs is an important concern in afforestation efforts. There have been extensive efforts to use Haloxylon ammodendron in many desert areas throughout the world in desert combating projects, but these efforts have not always been successful, despite high costs. In this study, we propose a new application of fuzzy decision-making method for selecting suitable sites for the growth of this species. We determine, based on available autecological studies, the most effective factors in desert habitats, and a fuzzy membership function is designed for each of the factors. A suitability index is constructed by unifying the fuzzified factors. This model is then applied to an actual plantation area to evaluate the suitability of different parts of this trial area. Finally, the predicted results are compared to the actual rate of success, based on the canopy cover percentage. The coefficient of determination for the observed canopy cover percentage plotted against the predicted suitability values is higher than 98%, which demonstrates that the presented fuzzy decision-making approach is potentially a powerful tool in site selection for this and, probably, other species.     

Suppressive effect of composts from residual biomass on Pythium ultimum

Journal of Plant Diseases and Protection - Two experiments were established in the laboratory of the Department of Organic Farming and Cropping Systems and the greenhouse of the University of...     

Effects of a prebiotic, Immunogen®, on feed utilization, body composition, immunity and resistance to Aeromonas hydrophila infection in the common carp Cyprinus carpio (Linnaeus) fingerlings

This study evaluated the effects of a commercial prebiotic, Immunogen, on feed utilization, growth rate, immunity promotion and carcass composition of the common carp Cyprinus carpio fingerlings. The fingerlings were adopted for 2 weeks and then reared in triplicate groups in 250-l tanks (n = 15 per tank with average initial weights of 11.12 ± 0.55 g). The fish fed on five isonitrogenous and isoenergetic experimental diets containing different levels of Immunogen (0, 0.5, 1, 1.5 and 2.5 g prebiotic/kg diet) to apparent satiation thrice a day for 8 weeks. Weight gain showed no differences among the groups fed different Immunogen levels. Both feed efficiency ratio and protein efficiency ratio significantly (p < 0.05) increased with increasing Immunogen levels from 0.5 to 1.5 g/kg diet. The highest protein content (p < 0.05) was found in the fish fed a diet containing 2.5 g/kg prebiotic. Haematological parameters and plasma total protein concentration were also significantly higher (p < 0.05) in the fingerlings fed diets containing 1.5 and 2.5 g/kg prebiotic in relation to the control. The control fish contained the highest mean of total bacterial counts. The lowest mean (p < 0.05) of total bacterial counts was observed in the fish fed the diet containing 2.5 g/kg Immunogen. The present study reveals that a dietary Immunogen supplementation from 1 to 1.5 g/kg is capable to improve the feed efficiency and growth performance of C. carpio fingerlings as well as their resistance to A. hydrophila infection.     

Evolutionary characterization of hemagglutinin gene of H9N2 influenza viruses isolated from Asia

The full length hemagglutinin (HA) genes of 287 H9N2 AI strains isolated from chickens in Asia during the period 1994-2009 were genetically analyzed. Phylogenetic analysis showed that G1-like viruses circulated in the Middle East and Indian sub-continent countries, whereas other sublineages existed in Far East countries. It also revealed G1-like viruses with an average 96.7% identity clustered into two subgroups largely based on their time of isolation. The Ka/Ks ratio was calculated 0.34 for subgroup 1 and 0.57 for subgroup 2 indicates purifying/stabilizing selection, but despite this there is evidence of localized positive selection when comparing the subgroups 1 and 2 protein sequences. Five sites in HA H9N2 viruses had a posterior probability >0.5 using the Bayesian method, indicating these sites were under positive selection. These sites were found to be associated with the globular head region of HA. To identify sites under positive selection; amino acid substitution classified depends on their radicalism and neutrality. The results indicate that, although most positions in HAs were under purifying selection and can be eliminated, a few positions located in the antigenic regions and receptor binding sites were subject to positive selection.     

Genetic diversity evaluation of wild Persian shallot (Allium hirtifolium Boiss.) using morphological and RAPD markers

Persian shallot, a bulb producing plant from Alliaceae, is a wildly growing plant collected for its bulbs. Bulbs of Persian shallot, called “Mooseer” in Farsi, are oval, white skinned, usually of one and rarely of two main bulbs and are completely different from common shallot (Allium ascalonicum). There is no information about genetic diversity of this species; therefore, the diversity of 17 wild Persian shallot populations collected from different parts of Iran across the Zagross Mountains were evaluated by morphological and RAPD markers. Fifteen random decamer primers could amplify DNA well and produced polymorphic bands among populations. The most fragment number amplified by one primer was 27 out of which 15 fragments were polymorphic and the least was 11 with 6 polymorphic bands. At the similarity of 0.60 on dendrogram constructed on the base of RAPD data, the samples were divided into eight sub-clusters. The highest and lowest detected similarities were 0.73 and 0.49, respectively. Clustering based on morphological traits divided the populations into three groups. Result of cluster analysis based on RAPD data did not show any correlation with morphological characters based on Mantel’s test (r = 0.03). The mineral and fatty acid analysis for defining the nutrient composition of this plant also revealed some differences among populations.     

Callus induction and embryogenesis of alfalfa (<Emphasis Type="Italic">Medicago sativa</Emphasis> L.) using hypocotyl thin cell layer culture

This research is performed for evaluating the morphogenesis responses of thin cell layers (TCL) of alfalfa (Medicago sativa cv. Karysary) hypocotyls. TCLs (0.1–0.5 mm) were obtained from sterile hypocotyls that were cultured to SH medium containing various combinations of 2,4-D and kin (0, 0.5, 1, 1.5 and 2 mg/l). Unexpectedly, the percentage of callus induction (PCI) and Callus diameter (CD) were not affected by different concentrations of 2,4-D and kin. PCI was 100% without any correlation to hormonal combinations. Significantly the difference between concentrations of 2,4-D and kin for percentage of somatic embryogenesis (PSE) was observed (p < 0.01) so that, the maximum PSE occurred with 1.5 mg/l 2,4-D and without kin. The 2,4-D and kin interaction was not significant for PSE showing that each of these hormones affected by PSE independently. The number of embryoids (NE) was significantly different on the various concentrations of 2,4-D (p < 0.05) and maximum NEs were observed on 1.5 mg/l 2,4-D and without kin.     

Variation in the Fatty Acid Composition Between and Within Two Mantis Shrimp Species,Harpiosquilla harpax and Miyakea nepa: Impact of Season and Sex

ABSTRACT

Harpiosquilla harpax and Miyakea nepa are two out of 400 marine crustaceans commonly known as mantis shrimp. Mantis shrimp are commercially valuable and can be found in fish markets of some Mediterranean and many Asian countries. This study focused on a comparative analysis of variation throughout the year in regards to proximate and total fatty acid composition in the muscle of male and female H. harpax and M. nepa. The most abundant fatty acids identified in the muscle of both species were C16:0, C18:0, docosahexaenoic acid (DHA; C22:6n-3), eicosapentaenoic acid (EPA; C20:5n-3), and C20:4n-6. Results of this study revealed that the muscle fatty acid profiles of H. harpax and M. nepa were not significantly different (p > 0.05), except for C14:0, C16:0, C22:0, and DHA amounts, and were mostly influenced by sex within each sampling month. Generally, the muscle of H. harpax contained higher (p < 0.05) levels of DHA than the muscle of M. nepa. The male mantis shrimp, within each species and most of the sampling months, appeared to have higher (p < 0.05) DHA, total n-3 polyunsaturated fatty acid (PUFA), and PUFA/saturated fatty acid ratio compared to the females. Both species could be considered as a good source of n-3 PUFA in the human diet.     

Spatial analysis of soil surface hydraulic properties: Is infiltration method dependent?

The management of irrigated agricultural fields requires reliable information about soil hydraulic properties and their spatio-temporal variability. The spatial variability of saturated hydraulic conductivity, K_s and the alpha-parameter α_vG-2007 of the van Genuchten equation was reviewed on an agricultural loamy soil after a 17-year period of repeated conventional agricultural practices for tillage and planting. The Beerkan infiltration method and its algorithm BEST were used to characterize the soil through the van Genuchten and Brooks and Corey equations. Forty field measurements were made at each node of a 6 m × 7.5 m grid. The soil hydraulic properties and their spatial structure were compared to those recorded in 1990 on the same field soil, through the exponential form of the soil hydraulic conductivity given by the Gardner equation, using the Guelph Pressure Infiltrometer technique. No significant differences in the results obtained in 1990 and 2007 were observed for either particle-size distribution or dry bulk density. The mean value of α_vG-2007 was found to be identical to that of α_G-1990, while that of K_s-2007 was significantly smaller than that of K_s-1990. In contrast to the Gardner equation, the van Genuchten/Brooks and Corey expression was found to be more representative of a well-graded particle-size distribution of a loamy soil. The geostatistical analysis showed the two parameters, K_s and α_vG-2007, were autocorrelated up to about 30 and 21 m, respectively, as well as spatially positively correlated within a range of 30 m. Despite the difference in the mean values of K_s between the two studies, the spatial structures were similar to those found in the 1990 experiment except for the covariance sign. The similarity in autocorrelation ranges indicate that the spatial analysis of soil hydraulic properties is independent of the infiltration methods (i.e., measurement of an infiltration flux) used in the two studies, while the difference in the covariance sign may be linked to the use of two different techniques of soil hydraulic parameterization. The covariance values found in the 2007 campaign indicates a positive relationship between the two parameters, K_s and α_vG-2007. The spatial correlations of soil hydraulic parameters appear to be temporally stabilized, at least within the agro-pedo-climatic context of the study. This may be attributed to the soil textural properties which remain constant in time and to the structural properties which are constantly renewed by the cyclic agricultural practices. However, further experiments are needed to strengthen this result.     

A feasibility study of using two-component polyurethane adhesive in constructing wooden structures

This investigation was conducted to determine the feasibility of using a two-component polyurethane （PUR） adhesive, with special waterproof properties, in constructing wooden structures. We designed and conducted tests to compare the shear strength and adhesion performance of PUR with polyvinyl acetate （PVAc） adhesive on block-shear specimens constructed of oriental beech （Fagus orientalis L.）, fir （Abies alba Mill.）, poplar （Populus deltoides Bartr.）, white oak （Quercus alba L.）, sycamore （Platanus orientalis L.） and white walnut （Juglans cinerea L.）. The values of the percentage of wood failure were also determined in specimens constructed with each adhesive. The highest shear strength values of both adhesives were obtained in specimens constructed of beech, while the lowest shear strength values were obtained in fir and poplar specimens. Average shear strength of the PUR adhesive was 16.5% higher than that of the PVAc adhesive. Specimens constructed of fir, poplar and sycamore were characterised by the highest percentages of wood failure, whereas the lowest average percentages of wood failure were obtained in beech and oak specimens. With the exception of oak specimens, there was no statistically significant difference between percentage of wood failure among the PUR and PVAc adhesives. Generally, the PUR adhesive showed an acceptable adhesion performance on wood materials used in our study.     

Technological properties of glulam beams made from hydrothermally treated poplar wood

In this research, technological properties of glulam beams made from hydrothermally treated poplar (Populus deltoides) wood were investigated. Poplar wood blocks with dimensions of 6 (r)?×?10 (t)?×?73 (l)?cm³ were cut and hydrothermally treated in a stainless steel reactor at temperatures of 140 and 160°C for a holding time of 30?min. The treated wood blocks were initially air seasoned and then they were dried in a semi-pilot scale vacuum dryer to achieve moisture content (MC) of 12%. Conditioning of the treated and the untreated wood blocks was done prior to adhesive bonding. Afterwards the glulam beams (4 ply) were manufactured using polyurethane. In order to evaluate the physico-mechanical properties of the beams, density, equilibrium moisture content, water repellent effect (WRE), anti-swelling effect (ASE), mass loss (ML), wettability as well as surface roughness due to the hydrothermal treatment were determined in the treated wood and delamination, bond shear strength, tensile strength, MC and moisture-induced stresses as well as strains in cross-section of the beams were determined in the glulam beams. The results revealed that density, ML, ASE, WRE, modulus of elasticity, modulus of rupture and delamination were increasing and the others were decreased due to the hydrothermal treatment.